I usually purchase the same "weight" boxes from Bankers Box (#901-00789) that require a little more work to put together. Since these were easier to open and less expensive, I thought I would give them a try for my year end files. BOY WAS THAT A MISTAKE... These "are" easier to pop open, but don't have enought support so they are wobbly and bow at the bottom of the box as well as being weak on the sides when you lift them. These are definitely for lightweight storage only. If I had not needed them right away I would have returned them.